As a member of the yoga community for many years, I regularly hear claims made about how stretching affects the body. These claims vary widely, and I’ve heard everything from “stretching is a magical cure that will heal all of your ailments” to “stretching is damaging for the body, and therefore yoga is bad for us.”

I try to be as evidence-based as possible in my approach to yoga, so I’m naturally skeptical of claims that appear to lack scientific support. In order to clarify some of the truth versus fiction regarding stretching for both myself and the greater yoga community, I decided to consult with an expert who is extremely up-to-date on the most current scientific research on stretching.

Dr. Greg Lehman, BKin, MSc, DC, MScPT, is a Clinical Educator, Physiotherapist, Chiropractor, and Strength and Conditioning Specialist. He travels the world teaching his Reconciling Biomechanics with Pain Science course to health & fitness professionals. He is also the creator of the “Recovery Strategies” pain workbook, which is an amazing, informative, and free resource for anyone in pain. Greg’s work has had a profound impact on the therapeutic, fitness, and yoga/movement worlds, and I am incredibly honored to feature his insight on my blog!

YOGA & STRETCHING Q&A W/GREG LEHMAN

QUESTION 1: In the yoga world, there is a widespread claim that stretching can lengthen connective tissues like ligaments & tendons, causing them to become lax and leading to "joint instability". Is this a biologically plausible assertion?

ANSWER: There is no evidence that this actually happens. Pretty unbelievable, eh? There is certainly more evidence that suggests when you pull (apply tension) to connective tissue it responds by getting stiffer, stronger and sometimes thicker. Old research by Dr. Woo has shown this consistently. The only consistent thing that can make connective tissue less stiff is immobilization and injury. So, it is possible that people who gain massive amounts of flexibility may have at some point damaged their tissue.

If people feel “lax” because they stretch I would guess that it would be more of muscle or nervous system change. People may not have the strength in those ranges to control the motion rather than the idea that they lengthened connective tissue constraints.

QUESTION 2: What exactly does "stability" mean when it comes to our joints, and is there evidence to support that a lack of joint stability causes pain and/or dysfunction?

ANSWER: A stable joint system just means when it gets perturbed or jostled it comes back to its resting place. But, people have expanded the definition to mean that a joint just moves a lot when you don’t want it to move. Joint instability is a problem when a joint pops out of place and does not readily go back into place. It certainly does happen but I doubt it’s that common.

ANSWER: Not significantly, meaning 1-5% of max force production [if stretching immediately prior to a strength activity]. And since we regularly don’t need to produce max force it’s not really an issue. And you only get this transient force reduction when you hold a static stretch for 45 or more seconds. Some research (Blazevich) even suggests that these max force/power losses are mitigated or completely ameliorated provided you do a warm up.

There is no reason to think that long-term stretching will make you weak.

QUESTION 4: Aside from concerns about lengthening ligaments & tendons that we've already covered here, is it inherently injurious or damaging for the body to spend time in passive end range stretches? What about for someone with a connective tissue disorder such as generalized joint hypermobility (GJH) or Ehlers-Danlos Syndrome (EDS)?

ANSWER: I think with EDS it makes sense to limit those movements and get strong instead. That’s one of those conditions where shit really does pop out of place. But for other people, who cares if you hang out at end range. You are just applying tensile load to tissue (pretty much what strength training does but at other ROMs) and the tissue will adapt by getting stronger.

We aren’t made of taffy. We don’t really “stretch” that way with applied loading like end ROM stretching. I don’t think it’s injurious but you could certainly argue that there are better options to achieve health and mobility – like adding strength training or even resistance throughout the range of motion.

QUESTION 5: There is a growing dialog in the yoga world about the distinction between active & passive stretching, with a new emphasis being placed on the benefits of training active strength & control through our ranges of motion ("active stretching") and a de-emphasis being placed on passive stretching. The reasoning goes that if we have more passive ROM available at a joint than active ROM, we are more susceptible to injury because we lack "control" in those end ranges. Would you agree with this line of thought?

ANSWER: I think you should do both. I wouldn’t be worried about injury though. I don’t think most people are getting injured because they have lost “control” of the joint. Further, if you get injured because the joint suddenly goes to end ROM, it’s not strength at end ROM that would have helped you - it’s the strength and control that you needed before you went to end ROM.

QUESTION 6: Many long-term yoga practitioners have discovered through imaging that they have a hip labral tear, and yoga is often blamed as the cause of this tear. Given that yoga is a low-load activity and that a majority of people in general will develop an asymptomatic labral tear as they age [Ref, Ref, Ref, Ref], is a long-term yoga practice a likely cause of a hip labral tear?

ANSWER: Labral tears are common. Heck, they might even be beneficial for performance. It’s not unreasonable to think that ANY activity can predispose you to joint changes. They happen and I doubt there is much we can do about it. You will see labral tears and bony changes in most sports.

So should we stop physical activity because of the chance of a labral tear? No. There are way too many benefits from a movement practice that far outweigh the negatives of a potential increase in the chance of having a labral tear.

QUESTION 7: In terms of stretching physiology, I believe that many people conflate the "muscle spindle stretch reflex" (reflexive muscular contraction during a stretch) with "stretch tolerance" (tolerating the discomfort of stretching) in their minds. Could you describe the difference between these two phenomena? Do they both play a role in stopping us at the end range of a stretch?

ANSWER: I’m not sure to be honest. Stretch tolerance definitely plays a role as the stretch is stopped (in the experimental studies) when the participant says its too much. What happens with long term stretching is that you are able to go farther without there being a dramatic change in tissue qualities. Meaning we assume that the changes in ROM are due to your tolerance or perhaps habituation rather than a structural change.

The muscle spindle stretch reflex is assumed to not be occurring during end ROM stretching because in these studies they monitor muscle activity. Meaning, they try to make sure there is no measurable muscle activity that occurs at end ROM. We assume its just a passive resistance to stretch. However, it is plausible that there is minor amount of activity that isn’t being picked up and this could be “putting on the brakes”.

QUESTION 8: Do you believe there are ways in which passive stretching could actually be beneficial for the body on a musculoskeletal level? If so, how?

ANSWER: Yes. I think long term stretching is just passive tensile force and tension has the ability to create positive structural adaptations in tissue. Some (Kubo) have argued that passive stretching can make tendon more efficient. Others suggest that passive stretching influences muscle stiffness which might be good to balance the stiffness changes in a tendon that can occur with injury.

I certainly don’t view stretching as a negative which I once did. I think if you argue against stretching you are really not “against” stretching but more pro some other intervention. So, if you like to stretch and its helpful for you I would encourage you to keep it up.

THANK YOU AGAIN TO GREG FOR HIS GENEROSITY IN SHARING HIS KNOWLEDGE AND INSIGHT WITH THE YOGA COMMUNITY. I HOPE YOU FOUND THIS INTERVIEW INFORMATIVE AND HELPFUL FOR YOUR YOGA PRACTICE & TEACHING! -JENNILearn much more from Greg Lehman on his website here, and follow him on Twitter!

This list was curated by the innovative online magazine Shut Up & Yoga, and their list includes many of my other favorite yoga/movement teachers as well - including fully half of the special guest teachers in my online class library! (Do I know how to pick ‘em or what? :) )

Click here to check out the article, and to find out what my favorite word is and why (and much more, of course!) I hope you enjoy reading more about my perspective on yoga & movement, as well those of all of the other interesting and innovative teachers who were featured.

I’m more than excited to welcome our newest special guest teacher to contribute to my online class library: the amazing Lizette Pompa!!

I have been a huge fan of Lizette for a long time, and I was thrilled when she said yes to the idea of contributing some kettlebell + yoga flows to my online class library!

Using a kettlebell is one way that we yogis can bring a form of external load into our yoga practice, and Lizette does a great job of unifying the feeling of a yoga flow with the added load / "prop" of the kettlebell.

Lizette is a yoga teacher and yoga studio owner based in Uppsala, Sweden who loves to incorporate strength into her yoga classes. She is incredibly strong and dedicated to her yoga practice, and she inspires me every day with her posts on Instagram.

I hope you love her first practice in my library (which is only $8.99/month for unlimited access to all classes & you can cancel anytime, by the way!) I've already taken this class two times, and my body is verrry happy!

We are less likely to experience injuries because we’ve increased the load-bearing capacity of our tissues, we have more confidence and trust in our body (which can decrease the likelihood of pain), and research suggests that higher levels of strength levels are associated with increased longevity and long-term health!

So all of those are excellent reasons to load our body regularly. But as amazing as yoga is (and I personally love this practice!), yoga is actually a *low-load* activity.

(Obviously for an inactive person, yoga might offer enough load for some adaptations, but at some point, we all adapt to our yoga practice and plateau, you know?)

For all of the talk we hear these days about injuries in long-term yoga practitioners, the reality is that it’s most likely *underloading*, and not overloading, that is the root cause of the bulk of these injuries. Crazy, huh?

And that’s why my biggest wish for yogis in 2019 is to load their bodies more! This could come in the form of integrating more strengthening moves right into our yoga practice (see my online class library for tons of yoga classes that do this!), and/or in the form of yogis taking on other additional activities that involve higher & varying loads (i.e. weightlifting, rock climbing, etc - the possibilities are endless!)

Does stretching make our muscles longer? Does stretching weaken our tissues and de-stabilize our joints? Can “overstretching” give us lax ligaments? Does stretching apply enough stress to our tissues to make them stronger?

There are a lot (a lot!) of claims about stretching that tend to circulate in the yoga community, and not all of these claims are accurate! Did you know?

“Histology” is the branch of biology dealing with the study of the tissues of the body. And from what I can see in the yoga world, many of the claims that we hear about stretching simply don’t jive with what histology/science has revealed about the properties of human connective tissue (including ligaments & tendons) and muscle tissue.

I really appreciated it when the incredibly knowledgeable Greg Lehman stated this quote I’ve featured here during his presentation to us at Jules Mitchell’s 300-hr yoga teacher training that I recently completed. Thank you, Greg!

Depending on which yoga circles you tend to run in, you might hear the message that A) yoga is a panacea that gives our body everything it needs, or B) there a ton of things wrong with yoga and although it does have psychological and spiritual benefits, it doesn’t do much for us on a physical health & fitness level.

Now I’m exaggerating somewhat for effect here, but I do observe two distinct camps in the yoga world. As someone who started off my yoga journey in camp A and then later migrated to camp B for a time, I can certainly relate to both perspectives. But these days I prefer to take a realistic, evidence-based approach that is more nuanced than either camp A or B.

It’s a physiological fact that yoga doesn’t offer our body everything it needs to be healthy. (No single physical activity possibly could!) Those in camp A would be wise to reconsider this idealistic approach.

But at the same time, there are many fitness and health-based benefits that yoga truly does offer us that seem to be overlooked by many in camp B. As an example, I recently put out a survey via my Instagram account that asked people to respond with the ways they thought yoga was good for our body. I received many excellent responses, but to my surprise, no one mentioned any musculoskeletal/biomechanical benefits from the practice at all! The reported benefits were mainly psychological in nature, such as relaxation, time for introspection, improved body image, etc. But there wasn’t any mention of physical benefits such strength, flexibility, endurance, etc.

And so today I thought we could look at some classic core components of fitness and use research and critical thinking to determine if and how yoga includes these components. Once we understand which components yoga offers and which it doesn’t, we can then decide to either integrate some of the “missing” items into our yoga practice to the best extent that we can - or we can simply choose to partake in other activities that naturally do a great job of offering these components.

There are of course many other benefits of yoga beyond physical ones, but I’d like to focus on this category specifically because I feel that our yoga community could use some clarification on these points.

Flexibility - YES

It’s been well-established in the research that yoga does improve flexibility. This is because a typical yoga practice takes our joints through their end range of motion on a regular basis. Here are just a few references that support this: [Ref], [Ref], [Ref], [Ref], [Ref]

Of course there is a lot of nuance to this topic. Yoga doesn’t seem to improve flexibility for every person at all joints, and oftentimes additional techniques like directed muscle contractions during stretches can help increase flexibility more efficiently than classic yoga techniques alone.

Additionally, there is a growing discussion around the distinction between flexibility and mobility, with mobility being the preferred quality to pursue over flexibility. But because “flexibility” is the official term on most fitness component lists, let’s just keep this discussion simple and consider flexibility to be about range of motion (ROM), and we’ll assume that in general, most of us could use to increase our ROM, at least at some joints.

And with that said, yoga in general has been shown to reliably improve flexibility in most people!

Strength - YES, but limited

Yoga can definitely offer muscle strengthening benefits, but they are limited. For example, yoga does strengthen the upper body in a “pushing” direction of movement (think pushing the floor away in plank pose or chaturanga), but it does not include significant strengthening in the “pulling” direction of movement (think pulling your body toward something, like a pull-up).

Additionally, because yoga involves bodyweight only, it can definitely strengthen our body up to a point. (And some yoga classes intentionally incorporate creative bodyweight strengthening moves to maximize this benefit for yogis.) But once our body adapts to the loads of our bodyweight, if we’re interested in further strengthening, we need to start using some form of external loading (i.e. weights or another form of resistance). To accomplish this, we could try incorporating some forms of external resistance into our yoga practice, or we could take on a separate weightlifting practice, which is a physical activity whose very “job” is to increase strength.

Muscular Endurance - PROBABLY, but just to an extent

Muscle endurance is a distinct category from muscle strength (although there is some natural overlap between them.) Whereas muscle strength is defined as the amount of force that a muscle can generate against resistance, muscle endurance has to do with a muscle’s ability to sustain a submaximal contraction for an extended period of time without fatiguing.

Does yoga increase muscle endurance? From my look at the research, I didn’t find an abundance of high-quality studies that examined this, but the studies that I did find seemed promising. These two studies [Ref, Ref] both saw muscle endurance increase in their experimental yoga groups. I also found two studies on Pilates mat exercises (different from yoga, but similar in that they use bodyweight only and no equipment), and in these studies muscle endurance also increased from the practice [Ref, Ref].

Additionally, based on my understanding of how muscle endurance works, I would imagine that regularly practicing sustained standing pose sequences would build muscle endurance in the lower body, as would repeatedly practicing vinyasa-type sequences for the upper body.

Power - NO

It’s tempting to equate the term power with the term strength, but in fitness terms, these are two separate (although related) qualities. Whereas strength means the amount of force a muscle can generate against resistance, The term power means how fast you can exert the strength that you have.

Power might start to make more sense if you consider some activities that typically utilize it: sprinting, swinging a baseball bat, and playing basketball all require an element of generating force very quickly. In order to train for power, activities like plyometrics (jump training) and dynamic kettlebell work are often recommended.

Yoga, by contrast, is a slower-paced activity. Even faster “power yoga”-type classes (no pun intended!) are still slower in speed than the fast, explosive movements of power-based training. One could possibly argue that jumping back to chaturanga might be a power-type activity because it’s done quickly and utilizes strength - but this isn’t enough to qualify yoga as a “power”-building activity in my opinion. If you’re looking to train the element of power, there are many other activities that are excellent at offering this!

Balance - YES

Yoga includes many poses that naturally challenge our balance, including high lunge, warrior 1, and all of the single-leg standing balance poses (tree pose, dancer pose, etc.) It seems like common sense to assume that yoga would therefore have positive effects on balance, but research has actually demonstrated this to be the case as well [Ref], [Ref], [Ref], [Ref], [Ref].

As we age, the risks from taking a fall can actually be quite detrimental to our health and well-being, so yoga’s potential to help us improve balance is a very valuable benefit on a functional level.

Additionally, when we take arm balances and inversions into account, yoga also helps us to work on balance with our hands as our base of support. So yes, in many regards, yoga helps us to improve balance!

Proprioception, Body Awareness, Body Maps - YES

Proprioception is your sense of how your body is arranged in space, and it’s intimately connected with the “body maps” in your brain, which are neurological representations of all of the parts of your body. The more accurate your body maps are, the better your proprioception, body awareness, and quality of movement in general.

I didn’t find a plethora of good studies on yoga and proprioception (although proprioception is included in the discussion of some of the studies on yoga and balance that I included in the “balance” section.) However, given that yoga is a low-load activity that tends to be practiced slowly, mindfully, and with control, it would stand to reason that it has the potential to improve our proprioception and to help clarify our body maps in our brain.

Cardiovascular Endurance - POSSIBLY, to a minor extent

Most of us are familiar with the idea that a “cardio” or “aerobic” activity is one that has the heart rate elevated for a sustained amount of time. Classic cardiovascular endurance activities include running, swimming, and biking.

Based on our understanding of how these aerobic activities look and feel (elevated heart rate, sweating, shortness of breath, lots of exertion), it seems clear that yoga is not a cardiovascular fitness practice to the same degree as these other classic activities. However, depending on the pace of the yoga practice, I believe that some yoga classes could be considered low-intensity cardiovascular activities.

In fact, this recent study [Ref] compared “high speed yoga” to “standard speed yoga” and found that “high-speed yoga results in a significantly greater caloric expenditure than standard-speed yoga. High-speed yoga may be an effective alternative program for those targeting cardiometabolic markers.”

Other research on this topic is mixed. These two studies [Ref], [Ref] did not support the idea that yoga could be considered cardiovascular exercise, but the type of yoga examined did not appear to be a very intense form. These two studies [Ref], [Ref] were more favorable to the idea - although the first one would be stronger evidence if it had included a control group.

My feeling is that if the style of yoga you’re practicing includes faster pacing and causes you to feel like you are moderately exerting yourself for a sustained amount of time, that practice could be considered a form of low-intensity cardiovascular exercise.

On a related note, I found a thorough research review that looked at 69 studies on whether yoga reduced the risk of cardiovascular disease and metabolic syndrome, and it concluded that “there is promising evidence of yoga on improving cardio-metabolic health” [Ref]. This isn’t answering the question of whether yoga improves cardiovascular endurance, but it does suggest that yoga can offer similar health benefits to cardio-type exercises!

IN SUMMARY…

The reality of yoga’s effects on the body is of course more nuanced than this generalized list. For example, a gentle yoga class will probably not include the elements of strength, muscular endurance, and low-intensity cardiovascular endurance - but it might include balance, proprioception, and flexibility. And a faster-paced vinyasa yoga class might include the elements that a gentle class doesn’t - but these won’t be endless, and they really do depend on what and how an individual teacher chooses to teach.

When making decisions about your own yoga and movement practices, consider yoga in the context of everything else that you do on a regular basis. For example, if you happen to trail run 2-3 times a week, you might not be interested in the potential cardiovascular benefits of faster-paced yoga classes; perhaps you would choose a slower-paced practice instead. If you strength train regularly at the gym, you might not need to focus on strength in your yoga practice; perhaps a gentle type of yoga is the right fit for you.

In general, the more that we appreciate yoga for what it does offer us while accepting what it clearly doesn’t, the higher our chances are of finding fulfillment in our yoga practice and balance and health in our bodies.

I am extremely honored to have the opportunity to host and share classes from so many incredible science-based yoga teachers in my online class library! Today I’d like to announce the newest teacher to join the ranks of this innovative teaching faculty starting on October 10, 2018.

For many people, Francesca Cervero doesn’t need any introduction. But for those of you who don’t know her, a few points of note are that she runs a thriving yoga teaching mentoring business, she specializes in The Science of the Private Lesson™, and she also hosts the popular Support & Strategy for Yoga Teachers podcast.

One of the reasons I’m extra excited about Francesca’s classes is that they were actually filmed with live yoga students! And because she is well-known for her impressive skill of holding space in the yoga room in a grounded way, these classes will be a very helpful window into watching this skilled yoga teacher do her space-holding work.

Francesca is also well-known in the yoga community for expertly teaching yoga classes without demo-ing any poses at all. Many people wonder “how does she do it?”, and now we can finally watch her in her element and learn from her techniques.

Look for her first class to arrive in the library on October 10th! I hope you love it!

Welcome to Part 2 of my interview with Rich Severin, PT, DPT, PhD(c), CCS on yoga and breathing misconceptions! As you might remember from last week, I recently reached out to Rich because I had accumulated a number of questions regarding claims about breathing that I commonly hear in the yoga world that seemed questionable to me. As a physical therapist and board certified cardiovascular and pulmonary clinical specialist, I knew that Rich would have an extremely informed perspective from which to address my questions. (Please see Rich's full bio included at the end of this piece!)

Today I present to you the much-anticipated second half of our Q&A. Between these two installments, I feel that this is a very valuable and fascinating offering for yoga teachers who are interested in becoming more evidence-based in their teaching. I hope that you enjoy, and don't hesitate to share your comments and thoughts below!

QUESTION 4: Is there an alignment relationship between the rib cage and the pelvis (or between the diaphragm and the pelvic floor) that ensures optimal physiological function in the body? We often hear in the yoga & movement worlds that it’s important that the diaphragm be "stacked above" the pelvic floor so that these two structures can move in concert during breathing. If the rib cage and pelvis are habitually aligned in such a way that these two structures are not “stacked”, can this result in pain (especially around the spine and pelvis) and/or dysfunction in the body?

ANSWER: Everyone’s anatomy is unique. Everyone’s anatomy is slightly asymmetrical. Everyone’s. Our bodies respond and make adaptations to stresses over time as well. The ability to respond and adapt/remodel while preserving physiological function is how we’ve survived as a species for thousands of years.

The ability to respond and adapt/remodel while preserving physiological function is how we’ve survived as a species for thousands of years.

— Rich Severin

Now that’s not to say that sudden or gross changes to posture can’t result in problems. It can and most of that has to do with exposing the body to stresses and loads exceeding its capacity or without enough time to make adaptions. It’s also not to say that just because someone has a slight deviation from our socially constructed (and not biologically constructed) ideal posture they will have pain or dysfunction. So no I’m not certain that I would agree with that statement or line of thinking.

QUESTION 5: Is there a known causal relationship between specific patterns of breathing (for example habitual “belly breathing”) and specific core conditions such as pelvic organ prolapse and diastasis recti?

ANSWER: Like I mentioned above there’s a lot of things that go into disease and dysfunction. I wouldn’t ascribe one mechanism to any disease or dysfunction. There is some research suggesting that individuals with COPD might have a higher risk for urinary incontinence and pelvic floor dysfunction but that’s at the extremes of respiratory muscle dysfunction. I don’t think most people in yoga are at that level of disease. However if one were to bear down long enough and they had pelvic floor weakness/laxity I could reasonably see a prolapse develop. However even in that example it’s not a one to one relationship. I would caution against making that sort of relationship.

QUESTION 6: In yoga class, we are always taught to breathe in and out through our nose rather than through our mouth. I can see how cultivating nasal breathing during yoga might slow the breath down and could therefore offer a meditative benefit to one’s practice. But are there significant physiological benefits to breathing through the nose instead of the mouth in a yoga practice - and in daily life in general?

ANSWER: Most people will generally breathe through their nose. Even those who use their mouth to breathe often still breath through their nose too. Nasal breathing is reflexive and as long as nasal airway resistance doesn’t get too high (like when you have a cold or congested nose), the lips maintain their seal and the tongue maintains contact with the back of the mouth cavity, you will breathe through your nose. Nasal breathing is innate and it allows us to warm, humidify and clean the air we breathe before it gets down to our lungs.

Nasal breathing is innate and it allows us to warm, humidify and clean the air we breathe before it gets down to our lungs.

— Rich Severin

The research is a bit limited and conflicting regarding whether mouth breathing or nasal only breathing is more efficient. Some studies demonstrate that nasal breathing is more energy efficient during exercise, however some have shown that there is no difference. Oral breathing definitely tends to dehydrate your oral passages and could make talking more challenging.

QUESTION 7: If someone desired to change their habitual way of breathing (i.e. breathe more into their rib cage and less into their abdomen, for example), how easily can she/he re-set the way that their autonomic nervous system controls their ~20,000 breaths per day?

ANSWER: There’s a lot to unpack in this question. Without diving into too much respiratory physiology, the cadence and depth (pattern) of your breathing is automatically controlled by the respiratory control center in your brain stem. The pattern of breathing can be modified by various sensory inputs to activate different neural circuits of the respiratory control center to modify the pattern to match the stress, activity or condition the body is undergoing. The most notable and potent sensory input is the pH of your blood and concentration of carbon dioxide (CO2) which are monitored by nerves called chemoreceptors. When pH or CO2 gets too high or too low, breathing cadence and depth will respond instantaneously in order to maintain a cellular environment conducive to metabolic work to keep us alive. The body is incredibly efficient and effective at this process, and control of pH will always “win”.

...the evidence that exists now does not suggest that we can change our pattern of breathing permanently due to the role breathing takes to keep us alive.

— Rich Severin

We can make temporary volitional changes to our breathing pattern. We can even temporarily stop breathing. However as I mentioned above the control of pH will always win. So while we can absolutely make these changes temporarily, the evidence that exists now does not suggest that we can change our pattern of breathing permanently due to the role breathing takes to keep us alive.

What many people might observe is that when one is stressed or in pain it usually results in hyperventilating or rapid breathing. This is due to our respiratory control center responding to the sensory and emotional inputs and thus selecting an according breathing pattern to match this “perceived threat”. By practicing slow breathing it may allow one to achieve a more relaxed state or distract themselves from pain or stress. If this relaxed state is achieved, the sensory input of a perceived threat has been absolved and different circuitry in the respiratory control center will be activated producing a more relaxed pattern of breathing. We’re finding that some of the circuitry used or involved in these breathing “programs” utilized might be hardwired.

QUESTION 8: The term “breathing dysfunction” is a commonly-used label in the yoga & movement worlds these days. Do yoga and movement teachers with no concurrent medical training have the authority and expertise to identify and label breathing dysfunctions and disorders?

ANSWER: Breathing dysfunction is a bit of a nebulous term. We encounter this issue often in physical therapy practice too. Unfortunately this term is often used cavalierly and done without performing a reliable, valid and objective assessment of breathing performance such as spirometry (lung volumes), respiratory muscle performance, pulse oximetry or arterial blood gases, and markers of ventilatory efficiency during exercise.

Visual inspection and manual assessment of breathing function are very subjective and are not sufficient to determine if someone’s breathing is dysfunctional.

— Rich Severin

Visual inspection and manual assessment of breathing function are very subjective and are not sufficient to determine if someone’s breathing is dysfunctional. So unless those objective measures mentioned previously are being used I would strongly caution against labeling anyone’s breathing as dysfunctional;e specially if they are walking and talking into your clinic or studio. Remember there are so many things involved with breathing and we generally do a pretty good job at it.

THANK YOU AGAIN TO RICH FOR HIS GENEROSITY IN SHARING HIS KNOWLEDGE AND INSIGHT WITH THE YOGA COMMUNITY. I HOPE YOU FOUND THIS INTERVIEW INFORMATIVE AND HELPFUL FOR YOUR YOGA PRACTICE & TEACHING! -JENNI

Rich Severin PT, DPT, PhD(c), CCS is a physical therapist and board certified cardiovascular and pulmonary clinical specialist. Currently he serves on faculty as a Clinical Assistant Professor at Baylor University in the Hybrid Doctor of Physical Therapy program and The University of Illinois at Chicago (UIC) Department of Physical Therapy as a Visiting Clinical Instructor. At UIC he also serves as the program coordinator for the Bariatric surgery rehabilitation program and is working on a PhD in rehabilitation science with a focus on cardio-respiratory physiology and obesity. He earned his Doctor of Physical Therapy Degree from the University of Miami. He completed a cardiopulmonary residency at the William S Middleton VA Medical Center/University of Wisconsin-Madison and an orthopedic residency with a focus on clinical research at the UIC. He has made scholarly contributions and presented both nationally and internationally on topics relating to cardio-respiratory physiology and clinical practice. He is an active member of the America Physical Therapy Association (APTA), The American Physiological Society and several other professional and scientific societies. He serves on the board of directors for Cardiopulmonary Section of the APTA as the chair of the communications committee and as a member of the nominating committee. Dr. Severin is also a member of the APTA Cardiopulmonary Section Heart Failure Clinical Practice Guideline development team, the Specialization Academy of Content Experts, and the editorial board for Cardiopulmonary Physical Therapy Journal. Follow him on twitter @PTReviewer.

As a member of the yoga community for many years now, I've heard a wide variety of claims about yoga and breathing. Some of these claims make a lot of sense, but others are confusing to me, and seem potentially dubious based on my understanding of human physiology. I have managed to accumulate several questions in my mind regarding beliefs about yoga and breathing, and I recently decided that it was time for me to consult an actual expert to offer some answers to my burning questions.

Rather than reach out to an established senior teacher in the yoga world, I decided to contact a respected authority on the topic of breathing who operates outside the realm of yoga. Rich Severin PT, DPT, PhD(c), CCS is a physical therapist and board certified cardiovascular and pulmonary clinical specialist. Currently he serves on faculty as a Clinical Assistant Professor at Baylor University in the Hybrid Doctor of Physical Therapy program and The University of Illinois at Chicago (UIC) Department of Physical Therapy as a Visiting Clinical Instructor. (Please see Rich's full bio included at the end of this piece!)

Because encouraging my fellow yoga teachers to become more evidence-based in their teaching is an important focus of my work, I naturally decided to share this valuable and informative Q&A session with my entire yoga community, so that we can all benefit!

I asked Rich a total of 8 questions, and today I'll share the first 3 of them with you. Next week we'll look at questions 4-8, which are equally informative and fascinating as the ones you'll read today. I hope that you enjoy, and don't hesitate to share your comments and thoughts below!

QUESTION 1: A typical yoga practice is a relatively low-load activity compared to activities such as weightlifting with heavy weights at the gym. At the gym, weightlifters use specific breathing strategies during their lifts to coordinate and control their IAP (intra-abdominal pressure) for core stability reasons. Given that yoga is a low-load activity, is core stability something that yoga practitioners should be concerned with, and if so, is there a conscious breathing strategy they should employ to ensure optimal core stability?

ANSWER: This is a great question. When lifting heavy loads such as a dead lift or squat close to 1RM (1 rep max) it is absolutely beneficial to use specific breathing techniques to help improve core stability. These are typically accomplished by drawing in a large volume of air into the lungs. Once the lungs are full intrathoracic pressure increases. This also causes compression of the abdominal contents. This stiffens the spine which in theory can help increase force output since the core is more “stable”.

You can see this technique used often across powerlifting and strongman competitions. You can even practice this yourself by taking a deep breath in and holding, notice how rigid your thoracic spine and abdomen becomes. I actually think this is why some individuals reflexively use the Valsalva maneuver when they are struggling trying to lift something heavy or themselves.

In regards to low load or low intensity movement like yoga, I don’t think it’s necessary or at least not for the purposes of core stability. Your body will reflexively and synergistically co-contract your core muscles prior to any movement. Focusing on breathing might be a nice way to get people to immerse themselves in the practice of yoga or whatever movement they are going through. Focusing on breathing may also help reduce anxiety and calm the mind; which as an amateur/retired Yogi myself can be useful especially when you’re trying a movement for the first time.

QUESTION 2: Belly breathing, in which one consciously displaces their abdominal contents during breathing so that the belly expands with their inhales, is often called “diaphragmatic breathing” in the yoga & movement world. Is this an accurate and helpful term for this type of breath? Why or why not?

ANSWER: I get a lot of flack for saying this but I honestly think diaphragmatic breathing is a bit of a misnomer. Your diaphragm is always active when you’re breathing, unless you're on controlled mechanical ventilation.

Now we can certainly voluntarily accentuate the displacement of different compartments (abdomen vs chest) when we breathe. However doing so doesn’t mean that we are turning the diaphragm “on”. We’re always using the diaphragm, it provides 75% of the inspiratory effort. It’s always “on” and since it provides the majority of the inspiratory effort, all of our breaths are really “diaphragmatic” even when it might not appear that way when we visualize someone breathing.

This ratio does change during exercise and in certain disease conditions but outside of those conditions this principle generally holds true. I tend to use the word belly breathing or deep slow breathing instead. I feel that patients understand those terms better and they accomplish the same goal without making things more complex and potentially inaccurate.

QUESTION 3: There are certain yoga breathing techniques that are claimed to strengthen the diaphragm. These include sustained breath retentions after the inhale and/or exhale (called “kumbhaka” in yoga) and also a diaphragm “pumping” style of breath called “kapalabhati”. Do techniques like these strengthen the diaphragm, and is there a physiological benefit for healthy people to work on strengthening their diaphragms (increasing this muscle’s ability to generate force) in the first place?

ANSWER: The diaphragm like other skeletal muscles responds to load. To strengthen it you have to place it under load and work it close to fatigue. This can be accomplished by breathing against a resistance, we call this inspiratory muscle training. This involves breathing through a device that has a valve which only opens once a predetermined negative pressure is generated from the patient breathing in. This is very useful for patients with inspiratory muscle weakness, such as patients with COPD, heart failure, morbid obesity as well as various neurological conditions such as Parkinson’s disease, spinal cord injury, and ALS. We determine the presence of weakness by measuring the maximal pressure a patient can generate from a breath in and comparing it to normative data. We’re finding that determining weakness is very useful because the patients that tend to benefit from inspiratory muscle training the most are those with weakness. Most healthy individuals or even individuals with disease and without inspiratory muscle weakness will probably only receive marginal and clinically insignificant benefits from this type of training.

However, for most healthy individuals it’s probably not going to improve strength because there isn’t a sufficient load or training stimulus to make adaptations.

— Rich Severin

The rapid breathing techniques you describe might result in marginal improvements in strength. I would liken them to performing a lift, like a biceps curl without resistance but doing so very quickly. In someone who has weakness, training this way might promote some minor increases in strength. However, for most healthy individuals it's probably not going to improve strength because there isn’t a sufficient load or training stimulus to make adaptations. It’s also important to note that regular/conventional exercise training will also result in improvements to inspiratory muscle strength.

...STAY TUNED NEXT WEEK FOR PART 2 (QUESTIONS 4-8) OF THIS YOGA & BREATHING Q&A!

Thank you again to Rich for his time and expertise in this Q&A. I really appreciated the clear and accessible manner in which he responded to my questions, and I hope that yoga teachers and students everywhere will find this information very helpful!

Rich Severin PT, DPT, PhD(c), CCS is a physical therapist and board certified cardiovascular and pulmonary clinical specialist. Currently he serves on faculty as a Clinical Assistant Professor at Baylor University in the Hybrid Doctor of Physical Therapy program and The University of Illinois at Chicago (UIC) Department of Physical Therapy as a Visiting Clinical Instructor. At UIC he also serves as the program coordinator for the Bariatric surgery rehabilitation program and is working on a PhD in rehabilitation science with a focus on cardio-respiratory physiology and obesity. He earned his Doctor of Physical Therapy Degree from the University of Miami. He completed a cardiopulmonary residency at the William S Middleton VA Medical Center/University of Wisconsin-Madison and an orthopedic residency with a focus on clinical research at the UIC. He has made scholarly contributions and presented both nationally and internationally on topics relating to cardio-respiratory physiology and clinical practice. He is an active member of the America Physical Therapy Association (APTA), The American Physiological Society and several other professional and scientific societies. He serves on the board of directors for Cardiopulmonary Section of the APTA as the chair of the communications committee and as a member of the nominating committee. Dr. Severin is also a member of the APTA Cardiopulmonary Section Heart Failure Clinical Practice Guideline development team, the Specialization Academy of Content Experts, and the editorial board for Cardiopulmonary Physical Therapy Journal. Follow him on twitter @PTReviewer.